Wireless networking systems have developed techniques to enhance service using feedback from subscribers. In some cellular telephone systems, for example, the mobile cellular telephone measures the quality of their reception and report results back to the base station. The base station uses this information to assign channels. Ideally, each cellular telephone is assigned to a channel that works well for that telephone.
Similarly, for radio data communication networks, the networked terminals can send information to peer, access point, and base station terminals about the quality of the channels that they are using and the quality of other channels that they can receive. This allows the system to allocate channels for more efficient use of the spectrum and to improve the quality of reception for many of the terminals.
In IEEE 802.16m, CQI (Channel Quality Indicator) feedback is sent on a CQICH (CQI Channel). The feedback is sent on an overhead channel and can be sent whether the MS (Mobile Station) is awake or asleep.